This invention relates to a process for the purification of an iron product by the removal of oxygen and sulfur therefrom and to mechanism for protecting refractories used in the steel making process.
As is well known in the steel making art, there are both batch and continuous process for making steel. Both of these processes utilize containers consisting of a support structure which may be steel or other high melting point materials with a protective liner to withstand the high temperatures of the steel making processes. The protective liners are usually selected from refractories. Because of the chemical nature of the slags used in the steel making process, the refractories may be attacked by certain chemical constituents of the slag.
Also, in the steel making art, a major problem is contamination of the molten metal with oxygen and sulfur. Heretofore, the removal of oxygen and sulfur from the iron product was effective to produce a melt containing somewhere in the range of between about 0.01 to 0.02 weight percent oxygen or sulfur. It has now been discovered with the process of the present invention that sulfur and oxygen concentrations in an iron product can be reduced to a few parts per million.
It has also been discovered that the refractories used in the steel making process and particularly those refractories containing magnesium whether as an oxide or a chromite can be protected against the presence of iron oxide which is corrosive to the presently used refractories and causing same to be replaced too frequently at great expenses.